Holsti, Kalevi J., author
Prentice-Hall, 1977
Buku Teks
Rourke, John T., author
McGraw-Hill, 2010
Buku Teks
Spero, Joan Edelman, author
Wadsworth, 2010
Buku Teks
Rourke, John T., author
Mc Graw Hill, 2009
Buku Teks
Griffiths, Martin, author
[publisher not identified], 1992
Buku Teks